[PATCH AUTOSEL 4.19 49/59] btrfs: remove BUG_ON(!eie) in find_parent_nodes

From: Sasha Levin
Date: Mon Jan 17 2022 - 22:40:36 EST


From: Josef Bacik <josef@xxxxxxxxxxxxxx>

[ Upstream commit 9f05c09d6baef789726346397438cca4ec43c3ee ]

If we're looking for leafs that point to a data extent we want to record
the extent items that point at our bytenr. At this point we have the
reference and we know for a fact that this leaf should have a reference
to our bytenr. However if there's some sort of corruption we may not
find any references to our leaf, and thus could end up with eie == NULL.
Replace this BUG_ON() with an ASSERT() and then return -EUCLEAN for the
mortals.

Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/btrfs/backref.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 0073182d4e689..3fe15d6f40873 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1313,10 +1313,18 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
goto out;
if (!ret && extent_item_pos) {
/*
- * we've recorded that parent, so we must extend
- * its inode list here
+ * We've recorded that parent, so we must extend
+ * its inode list here.
+ *
+ * However if there was corruption we may not
+ * have found an eie, return an error in this
+ * case.
*/
- BUG_ON(!eie);
+ ASSERT(eie);
+ if (!eie) {
+ ret = -EUCLEAN;
+ goto out;
+ }
while (eie->next)
eie = eie->next;
eie->next = ref->inode_list;
--
2.34.1